Electrical precipitator



F. SEIPP March 8, 1932.

ELECTRICAL PREC IPITATOR Filed March 29, 1930 5 Sheets-Sheet 2 I N VEN TOR.

A TTORNEYS March 8, 1932.. F, SElPp 1,848,579

ELECTRICAL PRECIPITATOR Filed March 29, 1930 3 Shee'cs--Shee'fI 3 INVENTOR. /f/'wnz je//b/.

A TTORNEYS Patented Mar. 8, 1932 UNITED STATES PATENT oFFl'cE FRANZ SEIPP, OF FRANKFURT-ON-'THE-HAIN, GERMANY, ASSIGNOB TO NTERNATIONAL PRECIPITATION COMPANY, F LOS ANGELES, CALIFORNIA, A CORPORATION OF CALIFORNIA ELECTRICAL PRECEPITATOR A Application led March 29, 1930, Serial No. 440,115, and in Germany Iay 28, 1929.

This invention relates to apparatus for the separation of suspended particles from gases 4 ordinarily extend substantially vertically and the gas to be treated may be caused to pass either downwardly or upwardly therethrough.

An important object of the present invention is to provide an electrical precipitator of this general type in which the collecting electrode pipes are provided with end portions at one or both endsthereof of novel shape such as to facilitate the mounting and interconnection of the ends of said pipes.

A further object of the invention is to provide an electrical precipitator of this type 1n which the en d portions of the collecting electrode pipes, at one or both ends thereof, aret so formed as to prevent or minimize electrical disturbances which would otherwise tend to occur at these points.

A further object of the invention is to provide an electrical precipitator of the above type in which the collecting electrodes are provided at their upper ends with suitably shaped sloping portions serving to connect together the upper ends of the pipes and provide a lower wall for the upper header or chamber of the precipitator, into which all of said pipes open. By so forming these slop-v mg portions that the lower wall of said upper header is formed entirely by sloping surfaces which are inclined downwardly toward the interior of the pipes closest adjacent thereto, the collection or building u on such surface of suspended material settling from the gas in the upper head is substantially prevented, thus eliminating electrical disturbances and other operating ditliculties which might result if such material were allowed to accumulate on thev lower wall of said upper header. Y

According to the present invention one or more of the above objects may be obtained by providing liared connecting members at one or -both ends of the collecting electrode pipes, said connecting members being round at one end and being connected at this end to the respective pipes, and being of .polygonal shape, such as rectangular `or hexagonal, at their other ends, and the connecting members of adjacent collecting electrode pipes having the substantially straight edges of their polygonally shaped ends connected together so as to form a continuous wall or partition forming a part of the header or gas distribution chamber into which said pipes open. 1nsofar as is consistent with the provision of proper supportingv members for the upper ends of the collecting electrodes and of rapping means for said electrodes, the polygonal ends ofthe flared connecting members of adjacent pipes are preferably directly connected to one another, but where this is impracticable additional connecting members may be provided therebetween. At the upper ends of the collectin electrode pipes, where the straight ed es o the polygonally shaped upper ends o the said connecting members are directly connected to contiguous edges for the adjacent pipes, the arrangement is such as to eliminate flat horizontal wall portions therebetween. Furthermore, where the spacing between adjacent rows of collecting electrode pipes, or between the outer collectin electrode pipes and the side walls of the upper header is so great as to make it impractical to extend the slo ing surfaces of said iared connecting members at the upper end of the pipes over the entire intervening space, I prefer to also provide the additional connecting members extending across such intervening spaces with sloping surfaces inclined downwardly toward the upper ends of the adjacent iared connecting members to which they are connected.

The connecting members may be connected, either detachably or integrally, with the ends of the respective collecting electrode pipes, and may also be connected, either degea tachably or integrally, with the additional connecting members which extend across the spaces therebetween and which coo erate therewith to form the bottom wall of t e upper header or the top wall of the lower header.

The accompanying drawings illustrate electrical preclpitation apparatus embodying my invention and referring thereto:

Fig. 1 is a horizontal section through the upper header of such an apparatus, looking down on the upper ends of the collecting elec trode pipes, this View being taken on section line 1-1 in Fig. 2.

Fig. 2 is a vertical section of the apparatus on line 2-2 in Fig. 1.

Fig. 3 is a vertical section on line 3-3 in Fig. 2.

Fig. 4 is an enlarged horizontal section on line 4-4 in Fig. 2.

Fig. 5 is a vertical section of the up er end portions of the collecting electro es,

taken on line 5-5 in Fi 4, with the discharge electrodes remove Fig. 6 is a similar view of the lower end connecting portions. g

Fi 7 is a view similar to Fig. 4, but showg 51e use of hexagonal connecting members for the collecting electrodes.

Fig. 8 is a vertical section of the upper end portions of the collecting electrodes, taken on line 8-8 .in Fig. 7, wit vthe discharge electrodes removed.

Fig. 9 is a similar view of the lower portions of the collecting electrodes.

The electrical preclpitator shown in Figs. 1 to 3 inclusive comprises an upper header 1 a lower header 2, provided with a hop er shaped bottom 3 having suitable means or removal of collecting material therefrom. a plurality of vertically extending collecting electrode pipes 4 extendin between said upper and lower headers, dlscharge electrode members, such as wires or finerods, extending axially within the respective collecting electrode pipes and supported and insulated from the collecting electrodes in any suitable manner, and passage means 6 and 7 connected respectively to the up er and lower headers for passage of as t rough the apparatus either downwar l or upwardly. The discharge and collecting electrode means may be connected, as by wires 8 and 9 respectively, to op osite sides of a source yof high voltage electrlcity, preferably unidirectional and the collecting electrodes are also preferably grounded as indicated at 10.

Each collecting electrode pipe is provided at its upper and lower ends with connecting members 11 and 12 respectively, as shown not only in Figs. 1 to 3 inclusive, but also somewhat more clearly in Figs. 4 to 6 inclusive. Each of said connedaing members is round at one end as shown at 11a and 12a respectively, for connection to the respective ends of the corresponding collecting electrode pipe,

and is shown as being square at its other end as indicated at 11b and 12b respectively, and is flared so as to provide smooth sloping surfaces 11c and 12e which are in each case inclined inwardly from the square end toward the collecting electrode ipe. Said flared connecting members are s own as connected to the collecting electrodes by means of bolts or other connecting members 13 extending through suitable ilanges 14, but it will be understood that if desired said connecting members may be formed as integral parts of said collecting electrodes. The collecting electrode pipes are shown as arranged in four rows indicated at A, B, C and D, and the connecting members of the two central rows Band C and of each of the outside rows A and D are shown as directly connected to one another at the adjacent edges of their polygonal end portions, as shown at 15, said edges of adjacent connecting members being in contiguous relation and being secured together in any suitable manner. However, in order to provide space for supporting members 16 and for sultable rapping means such as hammers 17 mounted on shafts 18, I have shown the rows A and Bas spaced somewhat apart and similarly for the rows C and D and it is therefore necessary to providel additional connecting means between the upper and lower ends of the collecting electrodes of these rows. At the upper end such additional connecting members are shown as comprising inverted V-shaped channel members 19 provided with oppositely slo` ing surfaces inclined downwardly towar the upper edges of the adjacent ared connecting members 11. At the lower end, however, such additional connecting members may comprise flat plates 21 whose edges are connected to the straight edges of the adjacent dared connecting members 12. Also at the upper end of the apparatus I have shown sloping connecting'members 22 which are inclined inwardly and downwardly from the side walls of the upper header to the outer edges of the outermost collecting electrodes. At the lower end, however, the space between the outer edges of the outermost collecting electrodes and the side walls of the lower header may be closed by flat members or plates 23. At the upper end, the additional sloping connecting members 19 and 22 may all be connected together to form an integral header plate, and similarly at the lower end, the additional connecting members 21 and 23 may all be connected together to form an integral header plate and the header plates so constituted may be connected, either detachably or integrally, to the edges of the adjacent connecting members 11 and 12 respectively.

The modification shown in Figs. 7 to 9 inclusive illustrates the use of connecting members whose outer ends are hexagonal instead of rectangular. The upper and lower connecting members at 11 and 12 respectively and each of said members is round at one end and connected at said end bers 19 and 21 are provided between .the

upper and lower ends of the two groups E and F and additional connecting members 22 and 23 are'also provided outside the ends of the collecting electrodes, to complete the walls of the upper and lower headers respectively. As before, the lower wall of the upper header is substantially free from horizontal surfaces, the connecting members 19 land 22 being provided with sloping surfaces inclined downwardly and inwardly toward the groups of collecting electrode pipes, and the surfacesof the connecting members 11 being also 1nclined downwardly and inwardlytoward the respective collecting electrodes. Iu this case the connecting members 22 and 19 are shown as integrally connected to the individual c onnecting members 11', while the connecting members 21' and 23 are integrally connected to the lower edges of the connecting members 12', thus forming integral top and bottoni header sheets, between which the collecting electrode pipes 4 may be connected, as shown. This form of apparatus is, perhaps, better adapted to the collection of liqulds than of solids, since it does no t lend itself so well to the provision of rapping means as does the construction shown in Figs. 1 to 6, although it would be understood that such rapping means, or other means for cleaning the electrode surfaces, may be provided if desired.

Inthe operation of the above described apparatus, using connecting members of either of the forms above described, the necessary high potential diilerence is maintained between the discharge and collecting electrodes in the usual manner of such apparatus and the as to be treated and containing finely divi ed suspended solid or liquid particles is passed either downwardly or upwardly through the apparatus, the electrical field serving to cause precipitation of such particles from the gas onto the electrodes and principally onto the surfaces of the collecting electrodes, and the precipitated material is caused to fall from said electrodes into the hopper or receiving means 3, either by the actioii of gravity alone or by the action of gravity assisted by suitable cleaning means such as the rapping hammers 17.

In the operation of such apparatus it has been found that if collecting electrode pipes of uniform diameter from their upper to their lower ends are used, there is a tendency for the production of back discharge from the upper and lower edges of said collecting electrodes, thus preventing vproper action of the electrical field at these points and'reducing the eliiciency of the apparatus. A particular advantage of the above construction is that the ared connecting members at the respective ends of the collecting electrode pipes prevent or minimize such disturbances, due to the fact that the distance from the discharge electrode to the surface ofthe collecting electrode orother parts connected thereto is gradually increased and the spacing of the polygonal ends of the connecting members from the discharge electrodes is suii'icientl to substantially prevent suchl back discharge.

Furthermore, lin the case of collection of suspended liquid particles the above effect is intensified at the lower ends of the collecting electrode pipes due to accumulation at this point of collected liquid running down the' surfaces of the pipes and building up to a certain thickness before falling therefrom to the vbottom of the precipitator housing. The above construction also prevents or minimizes disturbances from this latter cause, since even if the accumulated liquid should build up at the loweredges of the bottom connecting members, it would still be suiiiciently removed from the discharge electrodes to lfilalve nov disturbing effect on the electrical A further advantage of the above construction, which applies particularly to the upper end connecting members, is that the sloping surfaces of the flared connecting members, and of the additional connecting members eX- tending across. the intervening spaces between and around said flared connecting members, provide no flat or horizontal spaces for collection of solid or liquid material, and the bottom wall of the upper header is thus maintained at all times substantially clean and free from vsuch material. This is particularly advantageous when the gas is passed downwardly through the apparatus, since in that case the gas in the upper header'has a relatively high concentration of suspended matter, and the tendency for such matter to settle on any such horizontal surfaces is thereforegreater. The inclination of the entire Y directly connected to the additional connecting members which are provided for closing the intervening space between and around the groups of closely connected members.

I claim:

1-. An electrical precipitator comprising upper and lower headers, a plurality of round collecting electrode pipes extending vertically between said headers, and discharge electrode means extending within the respective pipes, each of said collecting electrode pipes having outwardly flared connectino members 'at the upper and lower ends thereof, said connecting members being round at the ends thereof which are connected to the 'collecting electrode pipes and being polygonal attheir other ends and the polygonal ends of the connecting member of adjacent collecting electrode pipes being contiguous with and connected to the polygonal end portion of adj acent connecting member.

2. In an electrical precipitator, a plurality of substantially vertical collecting electrode pipes provided with outwardly flared connecting members at one end, sald connecting members being round at one end and connected at said end to the respective pipes and being of polygonal shape at the other end, and adjacent connecting members having certain of the straight edges of their polygonally shaped ends directly connected together.

3. In an electrical precipitator having an upper header and a plurality of collecting electrode pipes extending downwardly from said header, connecting members secured to the upper ends'of the respective collecting electrode pipes, said connecting members being round at their lower ends and b`eing flared outwardly and upwardly and fhaving their upper ends of polygonal shape, certain of the straight edges of the polygonally shapedupper ends of adjacent connecting members being directly connected together.

v4L. In an electrical precipitator, a construction as set forth in claim Sand also comprising additional connecting means disposed around the upper ends of said connecting members and having surfaces sloping downwardly and inwardly toward said connecting members and secured at the lower edges to the upper ends of certain of said connecting members, the sloping surfaces of said connecting members and said additional connecting means constituting the lower wall of said upper header and being substantially free from horizontal surfaces.

In testimony whereof I have hereunto sub-- scribed my name this 1st day of March, 11930.

i FRANZ SEIPP. 

